I find the whole process utterly fascinating and reading this thread reminded me how much. As a species we obviously have a tremendous ability and need to create stories and have done since time immemorial. For me, I can go for ages with seemingly no inkling for a story, but it is as if I can feel the pressure building. The problem at that stage is the more I try to 'think of an idea for a story' the less likely it is that one will come.
Then suddenly, randomly one day, usually when I am doing something utterly mindless and nothing to do with writing, a little germ of an idea will appear. Or to use another metaphor a crack will appear in the dam holding back the story ideas that have been building, out of sight, in my mind. And that's it. Suddenly everything comes flooding out and ideas start automatically connecting themselves- characters spring to life and everything starts falling into place. The story grows, blossoms and builds and before I know it a new world of the imagination has opened up, beckoning me in. It's a magical feeling, even if when I actually get to writing it down it can sometimes be frustrating trying to recapture the purity and creativity of the original eureka moment.
And you see: just writing this and I start thinking, wait a minute... I could see that making a great story...
Anyone rips it off- just remember. I'm watching!